: 79 deville popping thru the carb

04-15-11, 08:27 PM
hi all, i'm having a problem working out the bug in my 79 deville. i bought it from a guy who had it in his garage for years, it didn't run when i bought it as it had been started for years. i've got it running now but it is popping thru the carb when i accelerate somewhat hard, also the 4 barrels don't seem to be kicking in properly. i've put in a new fuel filter, new plugs,wires and ignition module,cap and rotor. i had a friend time it to 38 degrees i believe and set the choke spring. the choke closes when cold and opens wide open when warm. When i first got it running it smelled of old gas terrible but now smells right on. I'm thinking the carb needs rebuilding but i'm wondering if i should run it on the road to clear it up. any imput would be appreaciated. thanks

04-15-11, 08:56 PM
My bet is on timing being off. Also, the secondaries won't open when you free rev it.

04-15-11, 09:25 PM
thanks csbucking. you may be right on the timing, i wasn't there when he timed it. and it started better cold before he timed it. i think it timed at 38 degrees before tdc, as on the engine info under the hood. the guy is good at certain things but he sometimes screws up technical stuff. as far as the secondaries i was running it on the road to test them and they will kick in but not right, maybe the timing being off could screw that up too

04-15-11, 11:37 PM
I'd put money on either bad timing (maybe a jumped tooth) or Bad plug wire routing (don't ask me how i know this lol!)

04-16-11, 02:01 AM
I forgot about the wire routing. The caddy motors are backwards from others. How does it idle? Find a routing diagram and make sure its right.

04-16-11, 09:25 AM
To set timing on these engines, you have to follow the instuctions to the letter. If you question anything, you should go back and make sure you understand what the instructions mean. Make sure all dashpots hold vacuum as they should. Did you replace the in carb fuel filter?

04-16-11, 07:09 PM
You might want to pull the rocker covers and see that all the valves are opening fully. Sounds to me like you have a lobe worn off the camshaft:bomb:

04-16-11, 07:45 PM
Where are you from? Perhaps someone from the forum can help you out or send you in the right direction. I also agree that the carb needs to be rebuilt and the timing sounds like it is too far advanced.

04-16-11, 11:00 PM
Thanks for responding guys. As of now i think the timing is off, the guy who did it for me just timed it without follwing proper procedures. i went into my repair manual and found out the correct timing(23 degrees BTD center and what vacuums to plug off. the firing order is correct as it runs and idles smooth, no skipping. i'll go from there and see what happens. the weather up here in northern ny is just terrible so i'll wait till it dries up abit. oh, and as far as a lobe being worn i'm not at that point yet, the guy who i bought it from told me the motor was rebuilt because of an oil issue. apparently one of the oil companies put out a batch of bad motor oil and they went good for some of the engines that got damaged. i do remember something about that years ago. and the motor does seem tight when it runs. not a knock one.the underbody of the car is remarkable considering where it cames from northern ny.

04-17-11, 09:11 AM
Be more specific as to your address. I'm in Western Mass. right across the border from a good portion of the Capital Area, as they call it. Willing to go as far as Troy or Watervelliet to help you out.

04-17-11, 07:01 PM
thanks for the offer deville33, but i'm along ways from the albany area. i'm on the northern ny canadien border. the town is ogdensburg which is about 200 miles from anywhere. seriously though i'll get her running, been along time since i played with a 70s vehicle. been working on 94-96 fwb for afew years. thanks anyway i appreaciate it

04-18-11, 08:05 AM
You might want to pull the rocker covers and see that all the valves are opening fully. Sounds to me like you have a lobe worn off the camshaft:bomb:

or a dead lifter. If you are getting a good popping through the carb it is almost always a bad cam or lobe. Sometimes they sound pretty cool but they aren't supposed to. If you take the valve covers off I'm sure you will see one rocker arm not moving much.

04-18-11, 09:49 PM
ok guys, i timed the car this morning and there is no more popping throught the carb, the car is running way to smooth for the lifter or lobe to be worn. actually it goes down the road real nice now, and it'll leave rubber on the pavement.thanks again